Compelling evidence exists that breast milk helps protect very low birthweight (VLBW; birthweight <1500 g) infants from prematurity-specific morbidities, including feeding intolerance, late onset sepsis, and necrotizing enterocolitis. Unfortunately, mothers of VLBW infants often exhibit delayed lactogenesis stage II (when the milk comes in) and inadequate breast milk production. Several small observational studies have linked earlier initiation of breast milk expression following delivery with greater milk production. However, no research has conclusively determined the optimal timing of breast milk expression to increase milk production or decrease timing of lactogenesis stage II. Without this evidence, practice guidelines cannot be developed to guide mothers who want to provide breast milk to their VLBW infants, and these mothers will continue to struggle with inadequate milk production for infant consumption. The overall objective of this 3-year study is to identify a strategy for enhancing breast milk production in mothers of VLBW infants to increase consumption of breast milk by their premature VLBW infants. The proposed study will follow a prospective cohort (N = 189) of racially and economically diverse mothers of VLBW infants for 6 weeks following delivery to test 1 primary hypothesis and 2 exploratory hypotheses. The primary hypotheses are related to the following: Earlier initiation of breast milk expression following delivery is associated with (1) earlier lactogenesis stage II, and (2) greater volume of breast mil production during the first 6 weeks. Exploratory hypothesis I is related to the following: Earlier initiation of breast milk expression is associated with a greater percentage of breast milk consumed by the infant during hospitalization and at discharge. Exploratory hypotheses 2 is as follows: Earlier initiation of breast milk expression following delivery is associated with a greatr volume of milk production during the first 6 weeks in infants born at 23-27 weeks gestation and those born at 28-32 weeks gestation. Following stratification according to the infant's gestational age, eligible women will be randomly assigned to one of three groups and instructed to start mechanically expressing their breasts, either in the first hour, 1-3 hours, or 3-6 hours following delivery. Timing of lactogenesis stage II will be documented, and volume of breast milk produced will be measured for the first 6 weeks. The percentage of breast milk the infant consumes weekly and at discharge will be measured. Results are expected to fill an important gap in research regarding the impact of timing of initiation of milk expression on milk volume, and timing of lactogenesis stage II in mothers of VLBW infants and the amount of breast milk their infant receives during hospitalization and at discharge. Results are also expected to provide new evidence regarding the impact of earlier initiation of milk expression in mothers delivering infants at differing gestational ages.